Tanning beds are large structures having a lower unit which houses a plurality of ultraviolet lights. The lower unit is relatively stationary and supports the weight of the operator who is being tanned. A movable top cover, which also houses a plurality of ultraviolet lights, is supported above the lower unit and must be raised to allow access by the operator and lowered to bring the ultraviolet lights of the top cover into close proximity to the operator.
There are various arrangements for supporting the top cover and raising and lowering the top cover relative to the lower unit. An earlier unit employed torsion springs for supporting the weight of the top unit. The operator raised and lowered the top unit manually with assistance from the torsion springs.
The top cover of the tanning bed is quite heavy. While providing an assisting force, such as torsion springs, to enable the operator to manually raise and lower the top cover, it is believed more desirable to make the raising and lowering completely electrically powered. However, electrically powered top cover raising devices desirably should exhibit several qualitites. First, loss of power should not allow the top cover to fall against the lower unit, possibly injuring the operator. Second, the operator should be able to move the top cover sufficiently to exit the lower unit in the event of a loss of power. Third, the supports which carry the weight of the top cover should be redundant, such that if one support fails, there is at least one other which will not only support the top cover but prevent it from tilting substantially so that it may not come in contact with the lower unit.